1. Field of the Invention
Embodiments of the present invention generally relate to reinforced resilient elements and more specifically, to reinforced resilient elements used in testing of semiconductor devices.
2. Description of the Related Art
Testing is an important step in the fabrication of semiconductor devices. Typically, partially or fully completed semiconductor devices are tested by bringing terminals disposed on an upper surface of a device to be tested—also referred to as a device under test (or DUT)—into contact with resilient contact elements, for example, as contained in a probe card assembly, as part of a test system. However, the reduction in the size of features formed on the DUT (for example, 50 microns and below) causes problems with the scalability of the resilient elements on the probe card. Specifically, the reduction in size of the resilient elements to facilitate contacting smaller features on the DUT increases the incidence of scrubbing off the contacting feature, or buckling and/or alignment problems with the resilient elements. Moreover, the reduction in size of the resilient elements increases the scrub ratio (defined as the amount of distance of forward movement across the contact feature to that of over-travel, or downward movement as the resilient element is moved past the point of contact with the DUT). The increase in scrub ratio of the resilient element restricts the over-travel budget required to establish proper electrical contact with the DUT without the resilient element scrubbing off the multiple DUT contact during probing. Moreover, multi-DUT testing with multiple resilient elements may require even greater probe over-travel to overcome non-planarity across the probing area to achieve simultaneous contact of all resilient elements.
Therefore, there is a need for an improved resilient element suitable for use in testing devices having smaller feature sizes.